Can someone else check my work?
on dice pin 38 and 54 if I put a multimeter on it, I get 5 volts sometimes and sometimes I get 5 volts then it drops to 0 volts when I turn the key to on.
Wis says it should always have 5 volts with ignition on.

pin38 is for the pressure sensor on my a/c. My a/c obviously works intermittent due to this phenomenon. I am thinking it is either the dice is crapped out and stops sending the 5 volts to the sensor. Or the ignition switch is to blame. The only problem I have is the a/c nothing else. I drive for about 5 miles then it just shuts down. everything simple has been tried.
or once I have drove it will not work again till it sits for about 30 to an hour.

Does that sound like a dice issue more then ignition? I am going to go play with jiggling the key to see if it bumps it up and down on the multimeter.

To add when I get a solid 5 volts on 38, then I get a solid 2-3 volts back on pin 9. Which is the signal back for the pressure level, reving the engine raises it which makes since as added heat and load add's pressure lol.

oh and jiggling the key had no effect I still only get a quick 5 volts at pin 38 then it falls to 0.

When I first got into the car this morning the a/c worked at idle for 15 minutes and I have a constant 5volts at pin 38. and pin 9 was giving me 2.0-3.0 volts. Then suddenly the 5 volts on pin 38 dropped to 0 and the a/c quit as well. I have been trying to figure this problem out since last summer.

new pressure sensor.
new evap sensor.
evac and recharged.
and can force the clutch to come on at clutch relay so its not the clutch or wiring to clutch.

The only problem I have is the a/c nothing else. I drive for about 5 miles then it just shuts down. everything simple has been tried.
or once I have drove it will not work again till it sits for about 30 to an hour.
.

I can't see why the DICE would fail in only one system...

Perhaps this is a heat related issue. Have you hade any diagnosis done with the Tech II?

Also - Someone mantioned this to me about a different vehicle..pehaps the expansion valve is seized...

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Ya that is why I did not replace it last summer lol I figure the odds of the dice failing in that nature seems pretty odd. I took it to Saab last week and they told me there is no software and when they try to flash the acc with software it freezes the tech 2 up. Which lead me back to thinking it was the dice.
Could possibly be the acc heater control. But why would the 5 volts disappear from a bad acc. Wis shows ignition on to be the only signal it should need to be present. I did unplug the radio and the acc unit to see if the dice would then give me 5 volts on that pin. Still the same problem. I also took the ground on my multimeter and ran it to a chassis ground to see if it was on the ground side of the dice. But it also caused the same problem. As I figured a loose ground may cause it.

I have an expansion valve, but have not changed it. When it runs the pressures look normal then when it stops they equalize pretty well. Wouldn't a clogged txv valve cause high pressure on high side, and low pressure on low?

I wish that was all it was. No its not the mixed air distribution, I checked that out. It is simply shutting the ac compressor off, like it is low on freon.

I tried to have it checked but the shop I had recharge it was closed and the shop that was open wanted 190 bucks cause they have to do a supposed complete system check plus charge. 25 per pound? fuuuuck you. I have a 30lbs cylinder in my shed i know how much r134a cost. Plus when I tell them its a saab 9-5 they go Ohhhh like they may not know how to work on it kind of owww. Like I'm gonna pay someone that has no clue about how the system works look at it and charge me for it lol.

The fact is the sensor is shutting my a/c off. I'm not sure if it is a freon problem or if it is the dice. Freon is 36psi low, and runs between 210-260 psi high side. Then high speed fan kicks on around 260 and pushes it back down to around 210.

equalized to 97psi low and high. its only about 66 degree's today.

I am sure it is code b2360. I just can't find why. I ohm'd the wires out as well for the pressure sensor. The sensor is brand new. Freon seems good. Though it hasn't set long enough to work again. I am positive it is the dice or acc. They were going to see what codes were stored but like i say. The tech2 said there was nothing. Not even a id number for the unit.

Hey... glad to hear you've made some progress on this. It appears that it'll be warm enough every day this week if we want to try switching ACC units to eliminate that as a possibility. I'll let you know my availability this week.

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The Q took a hard hit last race but managed to still finish well, a triumph to the spirit of this old bbq'ing jalopy. Will it be able to recover from the frame bending accident? Will it ever manifold BBQ again??